NY Well Driller cheat sheet

New York requires a minimum 50 ft separation between a private water well and a septic tank or absorption field; greater setbacks apply to other contamination sources under 10 NYCRR Subpart 5-1.

Bedrock wells in NY are typically completed in fractured crystalline or consolidated rock; yield depends on intersecting fracture zones, not on total rock porosity.

Overburden (unconsolidated) aquifers store and transmit water in pore spaces; typical NY settings include glacial outwash, kame and esker deposits, and river alluvium.

Hydraulic conductivity (K) describes a material's ability to transmit water; transmissivity (T) = K × saturated thickness (b) for a confined aquifer.

Darcy's law: Q = K × i × A, where i is hydraulic gradient (dh/dL) and A is cross-sectional flow area.

Drawdown (s) is the difference between static water level and pumping water level; specific capacity = pumping rate ÷ drawdown (gpm/ft).

A cone of depression forms around a pumping well; interference occurs when cones from adjacent wells overlap and reduce yield.

Groundwater generally flows perpendicular to contours of equal hydraulic head, from higher head to lower head.

Casing must extend from above grade to competent bedrock or to the required depth; the annular space is sealed with grout (neat cement or bentonite) to prevent surface and shallow contamination.

In NY, the well casing must extend at least 12 in. above the finished grade or floor and be capped with a sanitary well seal.

Well screen (or open borehole in bedrock) is placed opposite the producing zone; screen slot size is selected to retain formation material while passing water.

A gravel pack is placed around the screen in unconsolidated formations to increase effective porosity and reduce sand production; pack thickness is typically 2-4 in.

The sanitary well seal must be watertight and vented; the vent must be screened and turned downward to exclude insects and surface water.

Grout placement is normally done by the tremie (pump-down) method from the bottom up to avoid bridging and voids in the annular seal.

Pitless adapters allow the pump discharge line to exit the casing below frost line while keeping the well sealed and accessible.

Well capacity and pump setting must account for seasonal water-level fluctuation and the pumping water level, not the static level.

Cable-tool (percussion) drilling advances a borehole by repeatedly dropping a heavy bit; cuttings are removed with a bailer, and the method works well in glacial till and boulder formations.

Rotary air drilling uses compressed air to lift cuttings and is common for bedrock wells; foam or water may be added to control dust and stabilize the hole.

Mud rotary drilling uses a drilling fluid (bentonite slurry) to cool the bit, lift cuttings, and maintain hole stability; fluid properties (viscosity, density) must be monitored.

Reverse circulation rotary pumps drilling fluid down the annulus and up through the drill pipe, giving faster cuttings return in large-diameter holes.

Drilling fluid density must exceed formation pore pressure to prevent inflow, but excessive density can cause lost circulation and formation damage.

Casing is driven or set as the hole advances; the annular space must be sealed before the next interval is drilled to prevent cross-contamination between aquifers.

Well development after drilling removes drilling fluid, cuttings, and fines; methods include surging, jetting, bailing, and air-lifting.

Daily drilling logs should record hole depth, casing depth, formations penetrated, water strikes, and grout intervals for the completion report.

Development continues until discharge water is clear of sediment and the specific capacity stabilizes; over-development can cause formation collapse or sand production.

A pump test (constant-rate or step-drawdown) determines yield, drawdown, and specific capacity; a stabilized pumping water level indicates sustainable yield.

A short-term yield test is generally not sufficient to establish long-term safe yield; a longer-duration test is preferred for high-capacity wells.

Disinfection following construction typically uses a chlorine solution (commonly 50-100 ppm) held in the well for at least 12-24 hours, then purged.

Chlorine residual should be verified before and after the contact period; the well is flushed until chlorine is no longer detectable before sampling.

Bacteriological sampling must follow proper aseptic technique; a positive total coliform result requires investigation and re-disinfection.

Water-quality testing for new wells commonly includes coliform bacteria, nitrate, and other parameters required by the local health department.

Well yield is reported as gallons per minute (gpm); specific capacity (gpm/ft) is a useful indicator of well performance and formation response.

Submersible pumps are set below the pumping water level but above the well bottom; the pump intake must remain submerged during pumping to avoid cavitation and air entry.

A pressure tank maintains system pressure and reduces pump cycling; the tank precharge (air charge) is typically set 2 psi below the pump cut-in pressure.

Pressure switch settings define cut-in and cut-out pressures; the differential determines the operating pressure range (e.g., 30/50 or 40/60 psi).

A check valve on the pump discharge prevents backflow and loss of prime; multiple check valves may be required on deep settings.

Pump motor sizing must account for total dynamic head (static lift + drawdown + friction loss + pressure head) and flow rate.

Friction loss in drop pipe and fittings increases with flow; undersized pipe raises total head and reduces delivered pressure.

A pitless adapter or well seal must accommodate the electrical conduit and torque arrestor/cable guard to protect the pump cable.

Controls should include a low-water or dry-run protection where the pump could be exposed by declining water levels.

A well that is no longer used must be properly abandoned to prevent surface contamination from entering the aquifer through the open borehole.

Abandonment typically requires removal of obstructions, disinfection, and filling the entire well with grout (neat cement or bentonite) from bottom to top.

The casing is usually removed or cut off below grade; the top of the grout plug must be sealed and the site restored.

Abandonment records, including method, materials, and volumes, must be submitted to the appropriate NY authority.

Wells that are temporarily out of service may be maintained under a permit but must be protected from contamination and inspected periodically.

Grout must be placed by tremie to avoid voids; free-fall placement can bridge and leave unsealed intervals.

Abandoned wells that intersect multiple aquifers must be sealed so that contaminated water cannot migrate between zones.

Improperly abandoned wells are a common pathway for surface contamination and should be located and sealed during property development.

In New York, well construction and permitting requirements are administered primarily through 10 NYCRR Subpart 5-1 (drinking water supplies) and local health department rules.

A well completion report must document location, depth, casing, screen, grout, yield, and water quality; it is filed with the permitting authority.

Real property transfers often require disclosure of well location, condition, and water-quality test results.

Setback distances, casing depth, and grouting requirements are enforceable conditions of the well permit.

Water-well contractors must be registered with the NYS Department of Environmental Conservation (DEC) and comply with reporting requirements.

Public water systems are subject to additional NYSDOH requirements, including source approval and monitoring under the Safe Drinking Water Act.

Any change in well use, capacity, or abandonment must be reported and may require a new or amended permit.

Records of well construction and abandonment are public documents and should be retained by the contractor and the property owner.

Before drilling, call 811 to have underground utilities located; drilling near gas, electric, or sewer lines requires clearance and hand digging.

Confined-space entry into a well or pit requires atmospheric testing, ventilation, and a rescue plan; never enter without proper equipment and a standby person.

Drilling sites must control runoff, drilling fluids, and cuttings to prevent contamination of surface water and the well being constructed.

Electrical work on pump systems must follow the National Electrical Code and be performed by qualified personnel; lockout/tagout before servicing.

Personal protective equipment includes hard hat, safety glasses, hearing protection, gloves, and steel-toe boots; high-noise and dust exposures require controls.

Fuel and chemical storage on site must be contained and kept away from the wellhead and drainage paths.

Proper disposal of drilling fluids and cuttings is required; never discharge them to wetlands, streams, or storm sewers without authorization.

Documentation of safety training, inspections, and incidents supports regulatory compliance and protects the contractor and owner.